#app{
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
}

.progress {
  width:120px;
  height:20px;
  border-radius: 20px;
  background:
   linear-gradient(orange 0 0) 0/0% no-repeat
   lightblue;
  animation: progress 2s infinite steps(10);
}
@keyframes progress {
    100% {background-size:110%}
}